P0102 and P0151 help please

[OL RED]

Hey guys. My truck (1997 vortec 350) has had real bad hesitation for the past couple days. Finally today it gave me these codes:

P0102: MAF Circuit Low Input
P0151: O2 Sensor Circuit Low B2S1

Now it seems strange that I would be getting a low signal on both sensors. I checked all the fuses in the cab and under the hood. I searched for the wiring diagrams, but couldn't find one that showed both sensors.

I am curious if anyone knows if these sensors share a common ground, and where it might be?

Or if you have any other suggestions of things to check, I am all ears!

-Nick

 

[beardeddummy]

Check your fuses and 02 wiring harness.

 

[OL RED]

I did check the fuses in the cab and under the hood on the driver side. Are there other fuses to check for the sensors?

I will go check the o2 wiring now.

Thanks for your help
-Nick

 

[beardeddummy]

One of those fuses are labeled ecm or something similar double triple and quadruple check that is what I've seen be the cause

 

[Pj_stock]

Pull your electrical connector on your MAF sensor. Could be some corrosion in there. Your O2 sensor could be toast. How many km on the truck?

 

[OL RED]

Thankyou for the replies, I appreciate it.

Just for ***** I checked the fuel pressure. 60 psi key on engine off, 50 psi at idle, and jumped up to ~58 psi at full throttle. Changed the fuel filter and now all is good. I still don't understand how I got those codes.

-Nick

 

[racnredneck]

usually a bad ground wire for that shared circuit.. I se it all the time, usually more on the newer trucks though... check wring schematic for leas source and common relations .....

 

[OL RED]

Just a little update incase someone is brought to this thread by a google search.

The fuel filter did not solve all my problems, as the P0151 code came back.

Turns out that the ground strap on the passenger side head that goes to the frame had frayed and came apart. Replaced the strap and all has been well.

-Nick